Always use strictures (use strict; use warnings;). Oh, I already said that!

Your problem is/was that you are using = instead of == for testing numeric equality. Using strictures you'd have gotten the message:

the first time you tried running the code. It would have cost 30 seconds to add strictures and about 15 minutes or maybe a lot less (depending how big your actual code is of course) to clean up your code. Glancing at the times of your postings that would have given you about 1.5 hours you could have been drinking beer or reacquainting yourself with the wife instead of chasing frustrating bugs.